Author Topic: What's going on with consumer market products' PSUs?  (Read 4355 times)

0 Members and 1 Guest are viewing this topic.

Offline nunoTopic starter

  • Frequent Contributor
  • **
  • Posts: 606
  • Country: pt
What's going on with consumer market products' PSUs?
« on: May 07, 2018, 01:20:12 pm »
In the last year or so, I shifted occupation a little and also started repairing electronics in small appliances (such as dehumidifiers or peltier-based fridges) and air conditioned controller boards. And I already see a strong pattern: in 85%+ of the cases, the problem is in the mains AC to DC converter. Be it an indoors appliance or outdoors, old or new, the fault is most likely in the PSU.

I look at some of the controller chips datasheets and see that they're all full of protections, nevertheless some of those even roughly explode.

So, what's going on with consumer market PSUs? Bad components? Bad design? Bad implementation? Bad requirements? Bad mains? What? Please share your thoughts...
 

Offline b_force

  • Super Contributor
  • ***
  • Posts: 1381
  • Country: 00
    • One World Concepts
Re: What's going on with consumer market products' PSUs?
« Reply #1 on: May 07, 2018, 01:24:15 pm »
Saving just a few cents to much on the most critical parts and places in a design.

Offline Ampera

  • Super Contributor
  • ***
  • Posts: 2578
  • Country: us
    • Ampera's Forums
Re: What's going on with consumer market products' PSUs?
« Reply #2 on: May 07, 2018, 01:25:07 pm »
bust the PSU, and stupid people will keep buying your product.
I forget who I am sometimes, but then I remember that it's probably not worth remembering.
EEVBlog IRC Admin - Join us on irc.austnet.org #eevblog
 

Offline Miyuki

  • Frequent Contributor
  • **
  • Posts: 907
  • Country: cz
    • Me on youtube
Re: What's going on with consumer market products' PSUs?
« Reply #3 on: May 07, 2018, 01:33:24 pm »
It is simple just planned life  >:(

At PSU you can very easy plan how long it will work and when it bang, so marketing can easy say give us 3 year ones and 85%+ of them will die at third year
 

Offline bob225

  • Frequent Contributor
  • **
  • Posts: 259
  • Country: gb
Re: What's going on with consumer market products' PSUs?
« Reply #4 on: May 07, 2018, 01:35:28 pm »
One word. China

The lowest bidder wins the contract - use the cheapest components on the Shenzhen market, The biggest component failure on psu's are the caps
 

Offline TimNJ

  • Super Contributor
  • ***
  • Posts: 1661
  • Country: us
Re: What's going on with consumer market products' PSUs?
« Reply #5 on: May 07, 2018, 01:45:13 pm »
I don't think cutting corners on the power supply is a particularly new trend. It's probably the part of the system that is easiest to save cost on, and hardest to justify (to management, et al.) spending extra on. Why buy that 4A/12V Delta when you can buy 4A/12V Brand-X for 1/4 the price? MTBF? Doesn't matter as long as most of them last through the short warranty period.

Not as much as the power supply manufacturers' fault, as it is the companies looking for absolute bottom of the barrel prices.
 
The following users thanked this post: StuUK

Offline bob225

  • Frequent Contributor
  • **
  • Posts: 259
  • Country: gb
Re: What's going on with consumer market products' PSUs?
« Reply #6 on: May 07, 2018, 01:57:24 pm »
late 2000's Samsung products have major issues with caps, 2 year old 50" LCD got skipped for £2.50 worth of decent cap's as it was cheap to "replace it"

Hotpoint moved there control board manufacturing to Romania to cut costs, the supply side caps blow, and the soldering looks like its been done by a 5 year old

another issue I have come across is pcb quality - just show the iron to the board and it lifts the copper
 

Offline b_force

  • Super Contributor
  • ***
  • Posts: 1381
  • Country: 00
    • One World Concepts
Re: What's going on with consumer market products' PSUs?
« Reply #7 on: May 07, 2018, 02:04:08 pm »
I have seen mainly 85C caps were a good thinking person would use at least a 105C cap
Or similar issues like that (with inductors/transformers etc)

Online nctnico

  • Super Contributor
  • ***
  • Posts: 27006
  • Country: nl
    • NCT Developments
Re: What's going on with consumer market products' PSUs?
« Reply #8 on: May 07, 2018, 04:48:04 pm »
I have seen mainly 85C caps were a good thinking person would use at least a 105C cap
That doesn't have to be bad perse. There are long life 85C caps and short life 105C caps.

But in case of consumer equipment they probably opted for the cheapest one that gets the device through the warranty period. However in the EU a piece of equipment needs to have a reasonable life span so manufacturers don't get away with crap which just lasts until the warranty of over.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline TimNJ

  • Super Contributor
  • ***
  • Posts: 1661
  • Country: us
Re: What's going on with consumer market products' PSUs?
« Reply #9 on: May 07, 2018, 05:01:23 pm »
I have seen mainly 85C caps were a good thinking person would use at least a 105C cap
That doesn't have to be bad perse. There are long life 85C caps and short life 105C caps.

But in case of consumer equipment they probably opted for the cheapest one that gets the device through the warranty period. However in the EU a piece of equipment needs to have a reasonable life span so manufacturers don't get away with crap which just lasts until the warranty of over.

Just curious, is there some sort of minimum warranty for consumer products in the EU? i.e. If a company only states a 1 year warranty, then it can still get away with producing crap.

What's the incentive for the EU to do this? More reliable products = money savings for consumers = more spending power?
 

Online nctnico

  • Super Contributor
  • ***
  • Posts: 27006
  • Country: nl
    • NCT Developments
Re: What's going on with consumer market products' PSUs?
« Reply #10 on: May 07, 2018, 05:09:00 pm »
I have seen mainly 85C caps were a good thinking person would use at least a 105C cap
That doesn't have to be bad perse. There are long life 85C caps and short life 105C caps.

But in case of consumer equipment they probably opted for the cheapest one that gets the device through the warranty period. However in the EU a piece of equipment needs to have a reasonable life span so manufacturers don't get away with crap which just lasts until the warranty of over.

Just curious, is there some sort of minimum warranty for consumer products in the EU? i.e. If a company only states a 1 year warranty, then it can still get away with producing crap.

What's the incentive for the EU to do this? More reliable products = money savings for consumers = more spending power?
No minimum warranty in the EU is two years (Apple and Dell have paid hefty fines already for implementing this too slow). Other than that equipment must have a reasonable life span. If something fails too quickly the seller must pay part of the repair cost depending on how old the device is and how long it is supposed to last.
The idea is to reduce the amount of e-waste and get better value for money.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline nunoTopic starter

  • Frequent Contributor
  • **
  • Posts: 606
  • Country: pt
Re: What's going on with consumer market products' PSUs?
« Reply #11 on: May 08, 2018, 01:58:00 am »
This is all a very big problem, because the fixing cost is mostly work, so most appliances are going to the recycle/trash mostly working :scared: ...
 

Offline b_force

  • Super Contributor
  • ***
  • Posts: 1381
  • Country: 00
    • One World Concepts
Re: What's going on with consumer market products' PSUs?
« Reply #12 on: May 08, 2018, 08:41:24 am »
This is all a very big problem, because the fixing cost is mostly work, so most appliances are going to the recycle/trash mostly working :scared: ...
Welcome to a world were it's all about profit

Offline madires

  • Super Contributor
  • ***
  • Posts: 7803
  • Country: de
  • A qualified hobbyist ;)
Re: What's going on with consumer market products' PSUs?
« Reply #13 on: May 08, 2018, 10:23:05 am »
Other than that equipment must have a reasonable life span. If something fails too quickly the seller must pay part of the repair cost depending on how old the device is and how long it is supposed to last.
The idea is to reduce the amount of e-waste and get better value for money.

That's new to me. Just for your country or the whole EU? Any links?
 

Offline David Hess

  • Super Contributor
  • ***
  • Posts: 16657
  • Country: us
  • DavidH
Re: What's going on with consumer market products' PSUs?
« Reply #14 on: May 08, 2018, 12:05:27 pm »
I think they have just gotten better at designing for a specific operating life and warranty duration.  Aluminum electrolytic capacitors especially have become reliable "timers" based on ripple current rating and operating life so they can be "tuned" to fail at close to a specified time.
 
The following users thanked this post: Electro Detective

Offline schmitt trigger

  • Super Contributor
  • ***
  • Posts: 2228
  • Country: mx
Re: What's going on with consumer market products' PSUs?
« Reply #15 on: May 08, 2018, 01:19:04 pm »
I used to work for a power supply company, and my feeling was and still is, that for most customers power supplies are an afterthought.
They spend all the time and R&D dollars on the product itself (not a wrong thing to do, I might add) and then when the remaining budget will not allow anything more complex than a cord, they scramble fanatically to find the cheapest power solution.

A true story: a state of the art optical multiplexer/router. The main board was beyond awesome: a 10'' x 14", 8 layer board, crammed full with all sorts of esoteric and premium components. Gold plating everywhere. The sheer number of components and overall complexity was mind boggling.

It was powered from the cheapest power supply in our catalog, a PSU originally designed for a low cost printer.
The contrasts could not be more stark: the PSU board was a thru-hole, single sided CEM1 job.

Long story short: there were many factory failures. The root cause was that, to save a few pennies, they had specified that the DC output header to be unkeyed, meaning that the operators could by mistake reverse the connector while assembling the unit.

I suggested a keyed connector like the one in the photo, but the customer engineering never gave the approval. Citing backward compatibility issues, etc.

« Last Edit: May 08, 2018, 01:21:19 pm by schmitt trigger »
 

Offline b_force

  • Super Contributor
  • ***
  • Posts: 1381
  • Country: 00
    • One World Concepts
Re: What's going on with consumer market products' PSUs?
« Reply #16 on: May 08, 2018, 01:35:22 pm »
Yep, very recognizable story.
Of course that doesn't only counts for just PSU's but for many other things as well.

I guess that divides the really good products from the pile of mediocre stuff.

Offline Electro Detective

  • Super Contributor
  • ***
  • Posts: 2715
  • Country: au
Re: What's going on with consumer market products' PSUs?
« Reply #17 on: May 09, 2018, 01:28:00 am »
For those who wield a soldering iron competently:

Don't buy a product you can't get into easily, check out some Teardown videos or posts before dropping your cash   :clap:

No matter how good quality it appears to be and manufacturers golden rep is, order a better cap kit for it asap, label and store it appropriately   

Mark on your date calender two weeks after the warranty expires *

Fast forward * to that future date when the unit 'mysteriously'  misbehaves or claps out

Get out the cap kit, soldering rig and whatever your fav beverage is

Money well spent I reckon   :-+

« Last Edit: May 09, 2018, 01:31:09 am by Electro Detective »
 
The following users thanked this post: julianhigginson

Offline Cerebus

  • Super Contributor
  • ***
  • Posts: 10576
  • Country: gb
Re: What's going on with consumer market products' PSUs?
« Reply #18 on: May 09, 2018, 01:55:42 am »
No matter how good quality it appears to be and manufacturers golden rep is, order a better cap kit for it asap, label and store it appropriately   

Bearing in mind that the shelf life specifications of electrolytic capacitors are often significantly worse than their specified life under bias this may not be the wisest approach.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 

Offline JohnnyMalaria

  • Super Contributor
  • ***
  • Posts: 1154
  • Country: us
    • Enlighten Scientific LLC
Re: What's going on with consumer market products' PSUs?
« Reply #19 on: May 09, 2018, 02:20:29 am »
I have seen mainly 85C caps were a good thinking person would use at least a 105C cap
That doesn't have to be bad perse. There are long life 85C caps and short life 105C caps.

But in case of consumer equipment they probably opted for the cheapest one that gets the device through the warranty period. However in the EU a piece of equipment needs to have a reasonable life span so manufacturers don't get away with crap which just lasts until the warranty of over.

Just curious, is there some sort of minimum warranty for consumer products in the EU? i.e. If a company only states a 1 year warranty, then it can still get away with producing crap.

What's the incentive for the EU to do this? More reliable products = money savings for consumers = more spending power?
No minimum warranty in the EU is two years (Apple and Dell have paid hefty fines already for implementing this too slow). Other than that equipment must have a reasonable life span. If something fails too quickly the seller must pay part of the repair cost depending on how old the device is and how long it is supposed to last.
The idea is to reduce the amount of e-waste and get better value for money.

In the UK, the Consumer Rights Act of 2015 requires "goods to be of satisfactory quality" and:

(1) Every contract to supply goods is to be treated as including a term that the quality of the goods is satisfactory.
(2) The quality of goods is satisfactory if they meet the standard that a reasonable person would consider satisfactory, taking account of—
(a) any description of the goods,
(b) the price or other consideration for the goods (if relevant), and
(c) all the other relevant circumstances (see subsection (5)).

(3) The quality of goods includes their state and condition; and the following aspects (among others) are in appropriate cases aspects of the quality of goods—
(a) fitness for all the purposes for which goods of that kind are usually supplied;
(b) appearance and finish;
(c) freedom from minor defects;
(d) safety;
(e) durability.

Fair to say that I would consider very unsatisfactory premature power supply failure.
 

Offline rdl

  • Super Contributor
  • ***
  • Posts: 3667
  • Country: us
Re: What's going on with consumer market products' PSUs?
« Reply #20 on: May 09, 2018, 02:52:11 am »
I seem to remember a discussion here about the shelf life of electrolytic caps and that the general consensus was that they are likely to be as good as new even after 20 years or more.
 

Offline Electro Detective

  • Super Contributor
  • ***
  • Posts: 2715
  • Country: au
Re: What's going on with consumer market products' PSUs?
« Reply #21 on: May 09, 2018, 03:38:35 am »
My comment above assumed members here would go for good reputable capacitors with long-ish shelf life

and or use them for other projects in the meantime if required

and or in the rare event the product they were intended for actually went the distance via decent PSU components  :o

Hey, miracles can happen, right...?   :-//

 :D
 

Offline CJay

  • Super Contributor
  • ***
  • Posts: 4136
  • Country: gb
Re: What's going on with consumer market products' PSUs?
« Reply #22 on: May 09, 2018, 06:12:03 am »
Other than that equipment must have a reasonable life span. If something fails too quickly the seller must pay part of the repair cost depending on how old the device is and how long it is supposed to last.
The idea is to reduce the amount of e-waste and get better value for money.

That's new to me. Just for your country or the whole EU? Any links?

The whole EU.

https://europa.eu/youreurope/citizens/consumers/shopping/guarantees-returns/faq/index_en.htm

In the UK at least we actually have laws that better this, you can still claim for repairs during the expected lifespan of an item so, it could be up to six years.

But good luck finding a retailer who is willing to honour that without an argument, it's hard enough to get them to comply with the 2 year laws.

https://www.theguardian.com/money/2006/mar/25/consumernews.howtocomplain
 

Offline madires

  • Super Contributor
  • ***
  • Posts: 7803
  • Country: de
  • A qualified hobbyist ;)
Re: What's going on with consumer market products' PSUs?
« Reply #23 on: May 09, 2018, 09:30:19 am »
Thanks, but the first link is an FAQ about the 2 year EU legal guarantee. I'm interested in the prolonged period during which the seller has to pay the repair partly.
 

Offline CJay

  • Super Contributor
  • ***
  • Posts: 4136
  • Country: gb
Re: What's going on with consumer market products' PSUs?
« Reply #24 on: May 09, 2018, 10:03:33 am »
Thanks, but the first link is an FAQ about the 2 year EU legal guarantee. I'm interested in the prolonged period during which the seller has to pay the repair partly.

I would have thought that was implicit in the FAQ, it says several times that the seller must repair at no cost to the consumer so that would mean they must pay the repair cost if the repairer charges surely?
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf